2.7. Thermal stability
The thermal stability of the film sampleswas testedwith thermogravimetric
analysis (TGA; Hi-Res TGA 2950 thermogravimetric analyzer,
TA Instruments, New Castle, DE, USA). For this, 5 mg of each sample
was heated from room temperature to 600 °C at a heating rate of
10 °C/min under a nitrogen flow (50 cm3/min). A derivative form of
TGA (DTG) was obtained using differentials of TGA values, which was
calculated using a central finite difference method as follows: